Allowable expenses, samples and mileage, client disbursements and markups, VAT and MTD explained for UK self-employed interior designers.
Interior design is two businesses wearing one invoice. There is the creative trade: concepts, mood boards, space planning, schedules and project oversight that you charge as a design fee. And there is the procurement side: sourcing furniture, fabric, lighting, paint, flooring and fittings, often through trade accounts that the client never sees. The tax difficulty is almost never the design fee. It is the thousands of pounds of product flowing through your bank account that may, or may not, belong in your turnover, and getting that wrong inflates your numbers and pushes you into VAT years too early.
This guide is built around how designers actually earn and spend: the markup-versus-disbursement decision on goods, the sample, mileage and home-studio costs that make up real expenses, when VAT becomes unavoidable, and how MTD changes your record-keeping. Settle the procurement model first and everything downstream falls into place.
As a sole trader you pay Income Tax on profit, which is your total income minus allowable expenses. For 2025/26 the personal allowance covers the first GBP 12,570, then you pay 20% to GBP 50,270, 40% to GBP 125,140 and 45% above, with the personal allowance tapering away between GBP 100,000 and GBP 125,140 to create an effective 60% band. Class 4 National Insurance is 6% on profit between GBP 12,570 and GBP 50,270 and 2% above, with Class 2 NIC settled through Self Assessment.
Scottish designers pay Scottish Income Tax on their profit through six bands (19%, 20%, 21%, 42%, 45% and a 48% top rate) and carry an S-prefixed tax code, while National Insurance stays UK-wide. Welsh designers have a C-coded tax code at rates currently matching the rest of the UK. If your code looks wrong, perhaps because an old salaried design-studio job or a part-time PAYE role is distorting it, run it through the tax code checker.
This single decision shapes your tax return more than any expense, so settle it deliberately. When you buy furniture, fabric or fittings for a project, the money runs through your account one of two ways.
The markup model is simple to run and lets you profit on sourcing, but it inflates your turnover fast and drags you toward VAT registration. The disbursement model keeps purchasing out of your turnover, which can keep a busy designer below GBP 90,000 for longer, but the rules are strict: the cost must be recharged exactly, the client must really be the one buying, and you cannot dress up your own trade purchases as disbursements. Pick one approach per client, document it in your terms, and never mix them on the same project. When you do mark goods up, both the buy and the sell belong in your accounts, so use the multiple-income tax calculator if you also run separate fee and product streams.
Many designers begin alongside a studio job or do a few rooms for friends before going solo. The GBP 1,000 trading allowance is built for this. If your gross self-employed income from all design work is GBP 1,000 or less in a tax year, it is tax-free and you do not need to register for Self Assessment for it. Cross GBP 1,000 and you must register and report the full amount. If you are still treating this as a sideline, our guide to side hustle income explains how the threshold and reporting work alongside a main job.
Above the threshold you choose each year: deduct the flat GBP 1,000 allowance instead of working out actual expenses, or deduct your real allowable costs if they come to more. A designer with a serious software, sample and mileage habit almost always does better claiming actuals, but the allowance is handy in a very quiet first year.
An expense is allowable when incurred wholly and exclusively for the business. A designer's list spans creative tools, samples, travel and studio costs.
| Expense | What qualifies | Notes |
|---|---|---|
| Design software | CAD, SketchUp, AutoCAD, Adobe Creative Cloud, rendering and project-management subscriptions | Subscriptions fully deductible |
| Computer and devices | Laptop, large monitor, tablet and stylus, colour-accurate display | Usually claimed in full via the Annual Investment Allowance |
| Samples and swatches | Fabric sample books, paint testers, flooring and tile samples, finish boards | Allowable where used to win or deliver projects |
| Home-studio costs | HMRC flat-rate working-from-home allowance, or a fair proportion of heat, light, broadband, rent or mortgage interest | Choose the larger fair deduction |
| Premises | Studio or showroom rent, business rates, utilities | Allowable if you have dedicated premises |
| Mileage and travel | Site visits, showrooms, trade fairs, supplier warehouses, client meetings | 45p per mile to 10,000 then 25p, or actual vehicle costs |
| Insurance | Professional indemnity and public liability cover | Fully deductible |
| Memberships | BIID, SBID, BIDA and similar professional bodies | Allowable where relevant to the trade |
| Marketing | Website, portfolio photography, social ads, printed lookbooks, trade-show stand | Fully deductible running costs |
| Accountancy and bank fees | Bookkeeping, Self Assessment, business banking | Fully deductible |
Three costs dominate a real designer's expenses. Samples are easy to lose track of because they trickle out in small amounts: keep every sample-book and paint-tester receipt, as they add up over a year and are unambiguously business costs. Mileage is usually large because the job is mobile. Use HMRC's flat rate of 45p a mile for the first 10,000 business miles and 25p after that, which covers fuel, insurance, servicing and depreciation, and keep a log of dates, destinations and miles. Alternatively claim actual running costs apportioned to business use, but you cannot switch methods on the same vehicle once chosen. Home-studio running costs matter for the many designers who work from a spare room: use HMRC's simplified flat rate based on hours worked at home, or claim a fair proportion of actual household costs based on rooms used, then pick the larger.
The private share of dual-use broadband, phone, vehicle and devices must be excluded. Everyday clothing is never allowable even if you dress smartly for client pitches. Client entertaining and most hospitality are disallowed. Ordinary commuting to a fixed base is not business travel. And goods you buy purely on a client disbursement basis are not your expense at all, because they never become your trade purchases.
Take a designer who works on a fees-and-disbursement model, charging GBP 46,000 in design and project-management fees and recharging product to clients at cost (so it stays out of turnover).
Income: GBP 46,000 design and project fees
Allowable expenses:
Taxable profit: GBP 46,000 minus GBP 12,040 = GBP 33,960
Income Tax: GBP 33,960 minus GBP 12,570 = GBP 21,390 at 20% = GBP 4,278
Class 4 NIC: GBP 21,390 at 6% = GBP 1,283
Total tax and NIC: GBP 5,561 for the year. Because product is handled as disbursements, none of the resale value inflates turnover, which both lowers the headline figures and keeps this designer comfortably below VAT registration. Run your own numbers through the sole trader tax calculator to sanity-check.
For an interior designer, the costliest mistake is not a missed expense, it is running thousands of pounds of client furniture through your turnover when it should have been a disbursement. Decide the model before you buy, not at year end.
You must register for VAT once taxable turnover exceeds GBP 90,000 in any rolling 12-month period. The trap is that designers who buy and resell goods reach this far sooner than a fees-only consultant, because the full resale value counts as turnover, not just the design fee. A designer charging GBP 60,000 in fees but turning over another GBP 80,000 of marked-up furniture is well over the threshold even though the margin on the goods is thin.
Two levers help. First, the disbursement model keeps recharged supplier costs out of your turnover when you buy strictly as the client's agent and recharge at cost. Second, weigh who your clients are: if most are private homeowners who cannot reclaim VAT, registration adds 20% to their bill and may make you less competitive, whereas commercial clients reclaim it painlessly. If you do register, you reclaim VAT on your software, equipment, samples and overheads. Model the impact carefully before opting in voluntarily.
Making Tax Digital for Income Tax Self Assessment replaces the annual return with quarterly digital submissions and a year-end finalisation. The thresholds are based on gross income, not profit:
For a designer the gross-income test is the catch. If you buy goods on for clients at a markup, the full resale value is turnover, so you can be over GBP 50,000 of gross income even on modest fees, and that pulls you into MTD sooner than your profit alone would suggest. The disbursement model keeps pass-through purchasing out of the count. Practically, MTD means logging each fee, sample receipt and mileage trip digitally as it happens and sending HMRC a quarterly summary instead of one frantic January reconciliation. Our guide to MTD for sole traders walks through the quarterly rhythm in practice.
Mixing markup and disbursement on the same job. Decide per client whether goods run through your books or pass through as the client agent, and document it. Blurring the two distorts both turnover and VAT.
Running resold furniture through turnover without realising it triggers VAT. The full resale value counts, not just your margin, so designers cross GBP 90,000 far sooner than they expect.
Not logging mileage. Site visits, showrooms and supplier runs add up to thousands of deductible miles a year, but only if you keep a contemporaneous log.
Losing sample and tester receipts. They are small and frequent, so they slip through, yet they are unambiguous business costs that add up.
Assuming a PAYE allowance covers design income too. If a part-time studio job already uses your personal allowance, every pound of design profit is taxed from the basic rate up, so set money aside accordingly.
Tax guide for Vinted sellers in the UK: trading vs selling personal items, the GBP 1,000 trading allowance, allowable expenses, the platform data HMRC now receives, VAT and MTD.
UK Airbnb tax guide: the GBP 7,500 Rent a Room scheme, the GBP 1,000 property allowance, the abolition of furnished holiday lettings, allowable expenses, VAT and MTD for landlords.
The complete UK tax guide for Uber drivers: gross fares, mileage claims, Uber service fees, VAT, and what MTD for Income Tax means for you.
UK eBay seller tax guide: selling personal items vs trading, the GBP 1,000 trading allowance, eBay fees, the platform reporting rules, VAT and MTD.
Tax guide for self-employed hairdressers: chair rent, allowable expenses, mileage, VAT and MTD for Income Tax explained in plain English.
Everything self-employed taxi and private-hire drivers need to know about tax, mileage vs actual costs, VAT, and Making Tax Digital in 2025/26.
TapTax connects to your bank, categorises expenses automatically, and submits quarterly updates to HMRC. Free plan, no card required.
